The simultaneous wireless information and energy transfer (i.e., simultaneous transfer of information and energy in a wireless mode) is a new communication technology integrating the wireless communication technology and the wireless energy transmission technology. With the development of science and technology, the integration of the energy technology and the communication technology becomes a trend, which can not only realize a high-speed and reliable communication, but also effectively ease the pressure on scarcity of energy and spectrum, thereby having important application value in industry, medical treatment, infrastructure development, etc.
The simultaneous wireless information and energy transfer breaks through the traditional wireless communication means, takes energy attributes into consideration at the same time and integrates the wireless communication technology with the wireless energy transfer technology, thus enabling a parallel and simultaneous transfer of information and energy and having wide application value and innovation significance.
The simultaneous information and energy transfer may be used in various wireless terminals or devices which rely on batteries of limited capacity for power supply based on its characteristics, and feed the wireless terminals or devices by harvesting energy from signals, thereby greatly prolonging the standby time, decreasing the device volume and cost, and reducing the battery throughput significantly. Therefore, the environmental pollution caused during manufacture and recycling of batteries is greatly reduced. Based on the characteristics of non-contact long-distance transmission, the power supplied by batteries or cables can be replaced, and the convenience of the power supply is greatly improved. Based on the characteristics of stability and sustainability, the conventional way of harvesting environmental energy (such as wind energy, solar energy and kinetic energy) by energy harvesters can be replaced. Meanwhile, the simultaneous wireless information and energy transfer is widely applied in the improvement of people's life and brings about great social benefits. In the medical field, there is a serious problem of shortage of battery energy in implanting medical devices such as cardiac pacemakers and cardiovascular robots, the assembly of the simultaneous wireless information and energy transfer technology can protect patients form severe secondary pains.
In the application documents “TRANSMITTING SYSTEM AND RECEIVING SYSTEM FOR MULTICARRIER BROADBAND SIMULTANEOUS INFORMATION AND ENERGY TRANSFER” (Application No. 201510133784.X), “TRANSMITTING METHOD AND RECEIVING METHOD FOR SIMULTANEOUS INFORMATION AND ENERGY TRANSFER” (Application No. 201510133428.8) and “MULTICARRIER BROADBAND SIMULTANEOUS INFORMATION AND ENERGY TRANSFER OPTIMIZATION METHOD” (Application No. 201510133789.2), the inventor(s) has (have) proposed a simultaneous information and energy transfer method, wherein baseband signals transmitted by the system contain information baseband signals and energy baseband signals, which are both simultaneously transmitted after being processed correspondingly, and sufficient electric energy is provided to a receiving terminal through the energy signals. The method can be widely applied in the digital communication and analog communication.
In a simultaneous information and energy transfer system, in order to eliminate the intersymbol interference, a guard interval is inserted between each signal symbol to prevent intersymbol interference. The above simultaneous information and energy transfer system has the following two drawbacks:
First, since useful signals cannot be transmitted during the time of a guard interval, time resources of this interval may not be fully utilized, causing waste of resources and degrading the system performance at the same time; and
Second, since a receiving terminal of the simultaneous information and energy transfer system can only acquire energy from energy signals, in case that the receiving terminal requires an additional energy source, the system is unable to configure or provide the additional energy source flexibly.